Clinical Quick Reference Monthly / June 2023 Newsletter / Penicillin Shortages
Pfizer Issues Warning to FDA About Shrinking Penicillin Supply
This month Pfizer informed the FDA that two of its penicillin injectable products are in limited supply and may “stock out.”
The manufacturer warning relates to both penicillin G benzathine (Bicillin L-A) and penicillin G benzathine/penicillin G procaine (Bicillin C-R). These medications are used in the treatment of strep infections of the skin, nose, and throat; syphilis and syphilis-like infections; and the prevention of issues that can arise from certain infections.
Neither of the therapeutics is available in a generic form.
What Kind Of Medication Is Penicillin?
Penicillin is a drug used in the treatment of a wide range of infections.
Although some bacterial species have become resistant to penicillin, many kinds remain vulnerable. According to the NIH, penicillin is effective against numerous infections, especially those involving gram-positive cocci, gram-positive rods (e.g., Listeria), some anaerobes, and gram-negative cocci (e.g., Neisseria).
Are There Any Side Effects?
Both Penicillin V and G use can result in adverse effects. These may include abdominal pain, diarrhea, nausea, vomiting, rash, and even urticaria.
It is important to note that Penicillin G can also cause other adverse side effects such as muscle spasms, fever, chills, muscle pain, headache, tachycardia, flushing, tachypnea, and hypotension (NIH /2022).
Healthcare professionals should monitor and educate their patients accordingly about the risk of potential adverse effects.
Potential Adverse Effects
Hypersensitivity Reactions
A well-documented adverse effect that can occur with penicillin administration is hypersensitivity. This may be immediate or delayed.
With the “Immediate Onset” variety the reaction occurs within 20 minutes after receiving the medication. It is characterized by hives, itching, swelling (edema), laryngospasm, bronchospasm, hypotension, and vascular collapse.
In a “Delayed Onset” scenario the reaction may occur after 1 to 2 weeks of treatment. Symptoms of the reaction are fever, feelings of malaise, hives, myalgia, arthralgia, abdominal pain, and skin rashes.
Other reactions involve various organ systems.
Gastrointestinal System:
◦ GI symptoms are the most common effect of penicillin use. Reported symptoms usually involve nausea, vomiting, and stomatitis (observed with oral administration). Pseudomembranous colitis can also be an issue that sometimes arises during or after the treatment.
Hematologic Effects:
◦ If a patient receives doses over 10 million units/day and the patient has received a higher dose previously, this may precipitate Coombs-positive hemolytic anemia and neutropenia. The anemia and neutropenia resolve with cessation of therapy.
Metabolic System:
◦ The salt form of penicillin G can cause electrolyte imbalance.
For instance, hyperkalemia, when given in large IV doses.
Nervous System:
◦ Neurological effects related to the use of IV penicillin products could include hyperreflexia, myoclonic twitches, seizures, and coma. These are more likely to occur in patients that have impaired renal function.
Urogenital System:
◦ Large IV doses of penicillin can precipitate renal tubular damage in some patients.
Contraindications & Special Notes
Contraindications for the use of penicillin often relate to a previous history of severe allergic reactions to penicillin and its derivatives.
Penicillin is also contraindicated in individuals who have had Stevens-Johnson syndrome after administering penicillin or a penicillin derivative.
The penicillins are considered safe to use during pregnancy and nursing and the drug appears in very low concentrations in breastmilk.
Please note that per NIH documentation penicillin has an antagonistic effect when used with tetracycline and reportedly can lead to a 2.6 times greater risk of mortality when treating pneumococcal meningitis rather than using penicillin alone.
To learn more about penicillin and its derivatives, read more at the NIH link below:
https://www.ncbi.nlm.nih.gov/books/NBK554560/
To track FDA reported drug shortages, click here:
https://www.fda.gov/drugs/drug-safety-and-availability/drug-shortages
Disclaimer: The above study guide represents study materials. Always seek and follow the advice of your medical provider for any acute or chronic medical issues or questions. Always adhere to and follow the recognized protocols of your program or supervising agency.
Article Resources:
CDC
FDA
NIH
STAT PEARLS